Multi-compacting machine comprising three or more interarticulated units for soil tamping

ABSTRACT

A soil compacting machine comprising three interarticulated units, two of which are interconnected for universal relative swinging movement about three orthogonal axes, with hydraulic power means for effecting the swinging about at least two of these axes. The swinging between the other two units is also powered, the drive to the connections between the units being alternative so that when one pair of units is being swung relative to each other the other pair will idle, and vice versa.

United States Patent Domenighetti Oct. 21, 1975 [54] MULTl-COMPACTINGMACHINE 3,123,381 3/1964 Poore 280/492 COMPRISING THREE o MORE 3,215,21911/1965 Forsyth et al.... 280/492 3,443,826 5/1969 Hermiz 280/408INTERARTICULATED UNITS FOR SOIL 3,669,469 6/1972 Hartelius 230/492TAMPING 3,683,763 8/1972 Keppler et al. 94/50 R 7 Inventor: Domeniconomenighetfi, v 3,692,331' 9/1972 Vegors 280/492 Nosetto 6, 6500Bellinzona, Switzerland Primary ExaminerMervin Stein AssistantExaminer-Steven Hawkins [22] Flled' 1973 Attorney, Agent, or Firm-Young& Thompson [21] Appl. No.: 420,860

[57] ABSTRACT [30] Fore'gn Apphcatmn Pnomy Data A soil compactingmachine comprising three interar- Dec. 19, 1972 Switzerland tieulatedunits two of are interconnected for universal relative swinging movementabout three or- U-S. Cl. thogona] axes hydraulic power means for effect-Int. Clthe winging about at least two of these axes The ld 01 Search404/123, 128, 280/419, swinging between the other two units is alsopowered, 280/442, 49 403 the drive to the connections between the unitsbeing alternative so that when one pair of units is being 1 ReferencesClted swung relative to each other the other pair will idle,

UNITED STATES PATENTS and vice versa.

2,490,645 12/1949 Murat 280/492 2,933,143 4/1960 Robinson et al 180/14 7Clams 5 D'awmg F'gures MULTI-COMPACTING MACHINE COMPRISING THREE OR MOREINTERARTICULATED UNITS FOR SOIL TAMPING Machines provided with a centralarticulation type of steering are known and as compared to conventionalsteering self-propelled machines have substantial advantages, amongwhich are an accurate covering of the tracks being made on the soil bythe machine wheels, a high handiness and adaptability to various typesof soil.

It is the object of the present invention to make use of the aboveadvantages in a machine having not two, but three or more units that areinterarticulated and interconnected by articulated steering systems,such as those used on the most modern machines provided with centrallyarticulated steering.

According to the provided arrangements, a multiunit machine iscaterpillar configurated, capable of forward and rearward operation,insuring track covering, and can be driven by a single operator, whosedriving position can be selected, as desired, on any of the severalunits comprising the machine.

A use of particular interest for this machine is in selfpropelledtamping means.

Thus, it is desirable in such apparatus that the soil should beconcurrently subjected to the action of different tamping systems which,by simultaneously acting upon the same soil portion, will mutuallyenhance the effect thereof. It is already known, for example, that thereis an advantageous effect obtained by combining the action of avibrating metal drum and that of a set of highly loaded tired wheels.

According to the present invention, since three or more tamping unitscan be interconnected, still more satisfactory results can be provided,that is adding to the action of the two above mentioned means, also theaction of more or less vibrating sheepfoot or grid drums and the like.

An embodiment of the invention includes a centrally articulated combinedroller comprising a set of vibrating metal drums and a set of multipletired wheels, and a unit very similar to that provided with vibratingmetal drum and connected to the tired-wheel unit by a universal jointtype of steering, enabling the latter unit to rotate also about atransverse horizontal axis relative to the forward movement direction ofthe machine.

To enable a machine to enter a curve, such machines fitted with centralarticulated steering, normally use an actuator (hydraulic piston) which,by extending or retracting, causes the two units comprising the machineto rotate about the vertical axis of the steering articulation or joint.

Such an actuator is provided in multi-unit machines for each of theconnecting steering articulated joints; however, for accurate bothforward and rearward drive, these actuators are operated one at a timeby the control zone, while the other are not, thus remaining idle,

More particularly, when the entire machine is to be moved in a givendirection, the only actuator being driven is that at the first steeringarticulated joint in the movement direction. The other actuators areidle and therefore the third unit as well as the succeeding units behaveas actual mere trailers (this even if the (soil loading) rollingelements thereof which are in contact with the soil transmit atangential thurst force thereto).

When having to reverse the machine forward motion (which is very oftennecessary in machines of this design), all of the actuators are idle,except that of the steering articulated joint, formerly at the columntail, but now at the column head because of the motion reversal.

To provide for connecting and disconnecting the several actuators, adistributing valve is inserted in the oleostatic control system and iscontrolled through the main lever used by the operator for motionreversal.

When this lever is in forward running position, the forward firstactuator will be operated and the oil for all of the other actuators isshorted or shut off. Conversely, when the running reversal lever ismoved to reverse movement position, the distributing valve connectedthereto will comunicate the steering drive with the actuator formerly atthe tail and concurrently idle all of the other actuators.

The accompanying drawing shows by mere way of example an embodimentaccording to the present invention, and more particularly:

FIG. 1 is an elevational view showing a triple-drive self-propelledtamping roller comprising three interarticulated units, as hereinafterdescribed;

FIG. 2 is a plan view of the same machine;

FIG. 3 is a diagrammatic elevational view showing the steeringarticulated joint also enabling a rotation about a longitudinalhorizontal axis, as well as about a transverse horizontal axis;

FIG. 4 is a plan view of the articulated joint shown in FIG. 3; and

FIG. 5 shows the oleostatic system diagram for alternately operating thetwo actuators.

As it will be seen from the drawing, a tamping machine shown in FIGS. 1and 2 comprises a main unit 10 provided with an engine 11 and drivingposition 12 and bearing on the soil by a plurality of tired wheels 13.Instead of these multiple tired wheels, also a metal drum or otherrolling system could be used. This unit 10 is connected by aconventional steering articulated joint 14 to a unit 15 provided with avibrating metal drum 16 or other tamping means, the rotary movement ofwhich is provided by a power transmission system comprising a cardanshaft 17. When coupled to each other, as shown, the units 10 and 15herein described will appear as and perform the functions of a combinedtamping roller commercially known asCompact-O-Go. However, unlike theprior art combined tampers, the main unit also includes a secondsteering articulated joint 18 located at the free opposite side, bywhich a third tamping unit 19 can be held connected, which third unit 19is in turn provided with a rolling tamping means 20, preferably alsovibrating, and also rotatably driven by a motion transmission systemcomprising a cardan shaft 21. Both of the two steering articulatedjoints l4 and 18 are provided inter alia with horizontal actuators 22,23, serving the purpose of controlling and adjusting the mutual angle inthe horizontal plane for the three tamping units l0, l5 and 19.

While the steering articulated joint 14 is of conventional design and isthus not described herein, the articulated joint 18 is made to enablethe two units 10 and 19, as connected thereby, to rotate not only abouta vertical axis 24 (FIG. 3), but also about a longitudinal axis 25 andabout a transverse horizontal axis 26. Moreover, all of these threefreedoms of rotation must continuously controlled by the operator, so asto adjust these capabilities of rotation and to stop the same. To thisend, this joint could be made as shown in FIGS. 3 and 4, that isapplying a plate 27 to the free surface of unit 10, two identicalopposite rigid bearings 28 and 251 being carried thereon and supportingan element 30 rotatably carried about the vertical axis 24. Twohorizontal arms 32, 32 are mounted on said body or element 30, extendingabout the transverse horizontal axis 26 and at the ends thereof engagingthe element 33 comprising a cylindrical portion 34. Thus, this body orelement 33 is capable of rocking about the transverse horizontal axis26, but this rocking movement thereof is controlled by the actuator 35,the cylinder of which is rotatably mounted on said body 33, while theassociated piston is rotatably mounted on said element 30.

The cylindrical body or portion 34 has a coaxial cylindrical internalcavity, the axis 25 of which is longitudinally horizontal. A cylindricalbody 36 engages in said cavity and in turn is fast with the plate 37which is carried on the surface of the free wall of the tamping unit 19.In order to control the rotary movement for the two units and 19 aboutthe longitudinal horizontal axis 25, use is made of a latching device 38capable of stopping the relative movement.

The actuator 23 is used for controlling the rotation of the two units 10and 19 about the vertical axis 24.

As to the actuators 22 and 23, having the purpose of driving the rotarymovements for the tamping units 10, and 19 about the vertical axes 24and 39 of the steering articulated joints 18 and 14, these actuators maycomprise oleostatic pistons operable by admitting high pressure oil froma conventional servo-steering system.

However, according to the invention, these pistons will be alternatelyoperated in order to avoid undue slidings on the soil as would be causedby a concurrent drive of the two pistons.

According to the invention, only the first piston in the machine runningdirection will always be operated. In the case of two steeringactuators, such as in the embodiment shown in FIGS. 1-4, the actuator 22will be operated when the compactor is moving having the unit 15 as itsfront part, and at the'same time the actuator 23 will be disconnected.Conversely, still in the same. embodiment, when the machine is operatingin the opposite direction (and hence its front part is the tamper 19),it is the actuator 23 that should be operated, while at the same timethe actuator 22 will be disconnected.

FIG. 5 diagrammatically shows an oleostatic system according to theinvention, wherein reference numeral 40 designates the main oil tank,from which the oil is drawn by a pump 41 through a filter 42 anddelivered under pressure to a rotating distributor 43 operated by themachine steering wheel. Pressure oil reaches the distributor 43 througha piping 44 having a limiting valve 45 inserted therein. Normally, twopipings 46 branch off from the distributor 43 (of which one is adelivery piping and the other a return piping), directly leading to thesteering actuator.

According to the present invention, said pipings 4-6 enter atwo-position electro-distributor 47. At one of these positions, oil inpipings is directly supplied to the pipings 48 of actuator 24 and thepipings 49 of actuator 23 are shut off, whereby the piston stem 50 canfreely move without providing any resistance. When the distributor 47takes its other position, then the pipings 46 are directly connectedwith the pipings 49,

while the pipings 48 are shut off within the distributor 47, so that thepiston stem 52 for the actuator 24 can. freely move without providingany resistance. 7

The electro-distributor 47 takes either of the said two positionsdepending on whether the electromagnet 52 is energized or not byelectric power. To this endQthe electrical current from a power supply53 is supplied through electrical conductors 54 until. reaching a switch55 controlled by a cam 56, the latter being connected to a lever on thepilot bridge.

This lever 57 is for imparting forward and rearward movement to themachine and hence determines the running reversal.

From the switch 55 the electrical current passes through the conductors58 to the electromagnet 52.

By this system, the alternate energization for the two actuators isprovided according to the movement direction.

In this description, an exemplary operating mode for the actuators hasbeen explained, in which for the actuator control the position of thecontrol lever for running reversal is used, thereby providing a sort ofauto.- matic control.

However, it will be appreciated that this sort of automation could bealso otherwise obtained, as easily understood those skilled in the art.

What I claim is:

1. A multiple machine for compacting soil and the like, comprising threecompacting units interconnected by steering articulated joints, at.least one of said joints interconnecting the two adjacent units forrotation relative to each other about three orthogonal axes, and

2. A machine as claimed in clah4 1, and power means for swinging theother two units relative to each other about at least a vertical axis,and. means for selectively actuating the power means associated withonly one pair of said units at a time.

3. A machine as claimed in claim 1, said power means comprising meansfor selectively swingingsaid two units relative to each other about avertical axis and about a horizontal axis transverse to the path .ofmoveent of said machine.

4. A machine as claimed in claim 1, the connection of said two units forrotation about said three orthogonal axes comprising an upright bodymounted for rotation about a vertical axis on one of said units, acylindrical body mounted on said upright body for vertical swingingmovement about a first horizontal axis passing through said verticalaxis, and means secured to the other said unit of said two units androtatable on and relative to said cylindrical body about a secondhorizontal axis coaxial with said cylindrical body and perpendicular tosaid first horizontal axis and perpendicular to and passing through saidvertical axis.

5. A machine as claimed in claim 4, said second horizontal axis beingdisposed above said first horizontal 1 axis.

6. A machine as claimed in claim 4, said cylindrical body encompassingsaid means on said other unit, a hydraulic jack interconnecting saidcylindrical body and i said one unit to swing said two units relative toeach other about said vertical axis, and a hydraulic jackinterconnecting said cylindrical body and said upright selectivelyengageable between said cylindrical body body to swing said unitsrelative to each other about and said other unit to prevent rotation ofsaid units relsaid first horizontal axis. ative to each other about saidsecond horizontal axis.

7. A machine as claimed in claim 4, and latch means

1. A multiple machine for compacting soil and the like, comprising threecompacting units interconnected by steering articulated joints, at leastone of said joints interconnecting the two adjacent units for rotationrelative to each other about three orthogonal axes, and power means forselectively controlling the swinging of said two units relative to eachother about at least two of said three orthogonal axes thereby to permitcontrol by an operator of the position of said two adjacent unitsrelative to each other.
 2. A machine as claimed in claim 1, and powermeans for swinging the other two units relative to each other about atleast a vertical axis, and means for selectively actuating the powermeans associated with only one pair of said units at a time.
 3. Amachine as claimed in claim 1, said power means comprising means forselectively swinging said two units relative to each other about avertical axis and about a horizontal axis transverse to the path ofmovement of said machine.
 4. A machine as claimed in claim 1, theconnection of said two units for rotation about said three orthogonalaxes comprising an upright body mounted for rotation about a verticalaxis on one of said units, a cylindrical body mounted on said uprightbody for vertical swinging movement about a first horizontal axispassing through said vertical axis, and means secured to the other saidunit of said two units and rotatable on and relative to said cylindricalbody about a second horizontal axis coaxial with said cylindrical bodyand perpendicular to said first horizontal axis and perpendicular to andpassing through said vertical axis.
 5. A machine as claimed in claim 4,said second horizontal axis being disposed above said first horizontalaxis.
 6. A machine as claimed in claim 4, said cylindrical bodyencompassing said means on said other unit, a hydraulic jackinterconnecting said cylindrical body and said one unit to swing saidtwo units relative to each other about said vertical axis, and ahydraulic jack interconnecting said cylindrical body and said uprightbody to swing said units relative to each other about said firsthorizontal axis.
 7. A machine as claimed in claim 4, and latch meansselectively engageable between said cylindrical body and said other unitto prevent rotation of said units relative to each other about saidsecond horizontal axis.